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Finding the Fourth Proportional to 406.55, 561.30 and 308.75

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Solution

The fourth proportional to 406.55, 561.30 and 308.75 is: 426.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.55 : 561.30 = 308.75 : x
  2. Step 2: Convert to fraction form
    406.55/561.30 = 308.75/x
  3. Step 3: Cross multiply
    406.55x = 561.30 × 308.75
  4. Step 4: Simplify right side
    406.55x = 173,297.41
  5. Step 5: Solve for x
    x = 173,297.41/406.55
  6. Step 6: Final answer
    x = 426.26

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.